Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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sys/netgraph/netflow/netflow.c
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1 /*- 2 * Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org> 3 * Copyright (c) 2001-2003 Roman V. Palagin <romanp@unshadow.net> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $SourceForge: netflow.c,v 1.41 2004/09/05 11:41:10 glebius Exp $ 28 */ 29 30 static const char rcs_id[] = 31 "@(#) $FreeBSD: releng/6.0/sys/netgraph/netflow/netflow.c 146285 2005-05-16 17:10:08Z glebius $"; 32 33 #include <sys/param.h> 34 #include <sys/kernel.h> 35 #include <sys/limits.h> 36 #include <sys/mbuf.h> 37 #include <sys/syslog.h> 38 #include <sys/systm.h> 39 #include <sys/socket.h> 40 41 #include <machine/atomic.h> 42 43 #include <net/if.h> 44 #include <net/route.h> 45 #include <netinet/in.h> 46 #include <netinet/in_systm.h> 47 #include <netinet/ip.h> 48 #include <netinet/tcp.h> 49 #include <netinet/udp.h> 50 51 #include <netgraph/ng_message.h> 52 #include <netgraph/netgraph.h> 53 54 #include <netgraph/netflow/netflow.h> 55 #include <netgraph/netflow/ng_netflow.h> 56 57 #define NBUCKETS (65536) /* must be power of 2 */ 58 59 /* This hash is for TCP or UDP packets */ 60 #define FULL_HASH(addr1,addr2,port1,port2)\ 61 (((addr1 >> 16) ^ \ 62 (addr2 & 0x00FF) ^ \ 63 ((port1 ^ port2) << 8) )& \ 64 (NBUCKETS - 1)) 65 66 /* This hash is for all other IP packets */ 67 #define ADDR_HASH(addr1,addr2)\ 68 (((addr1 >> 16) ^ \ 69 (addr2 & 0x00FF) )& \ 70 (NBUCKETS - 1)) 71 72 /* Macros to shorten logical constructions */ 73 /* XXX: priv must exist in namespace */ 74 #define INACTIVE(fle) (time_uptime - fle->f.last > priv->info.nfinfo_inact_t) 75 #define AGED(fle) (time_uptime - fle->f.first > priv->info.nfinfo_act_t) 76 #define ISFREE(fle) (fle->f.packets == 0) 77 78 /* 79 * 4 is a magical number: statistically number of 4-packet flows is 80 * bigger than 5,6,7...-packet flows by an order of magnitude. Most UDP/ICMP 81 * scans are 1 packet (~ 90% of flow cache). TCP scans are 2-packet in case 82 * of reachable host and 4-packet otherwise. 83 */ 84 #define SMALL(fle) (fle->f.packets <= 4) 85 86 /* 87 * Cisco uses milliseconds for uptime. Bad idea, since it overflows 88 * every 48+ days. But we will do same to keep compatibility. This macro 89 * does overflowable multiplication to 1000. 90 */ 91 #define MILLIUPTIME(t) (((t) << 9) + /* 512 */ \ 92 ((t) << 8) + /* 256 */ \ 93 ((t) << 7) + /* 128 */ \ 94 ((t) << 6) + /* 64 */ \ 95 ((t) << 5) + /* 32 */ \ 96 ((t) << 3)) /* 8 */ 97 98 MALLOC_DECLARE(M_NETFLOW_HASH); 99 MALLOC_DEFINE(M_NETFLOW_HASH, "NetFlow hash", "NetFlow hash"); 100 101 static int export_add(item_p, struct flow_entry *); 102 static int export_send(priv_p, item_p); 103 104 /* Generate hash for a given flow record. */ 105 static __inline uint32_t 106 ip_hash(struct flow_rec *r) 107 { 108 switch (r->r_ip_p) { 109 case IPPROTO_TCP: 110 case IPPROTO_UDP: 111 return FULL_HASH(r->r_src.s_addr, r->r_dst.s_addr, 112 r->r_sport, r->r_dport); 113 default: 114 return ADDR_HASH(r->r_src.s_addr, r->r_dst.s_addr); 115 } 116 } 117 118 /* This is callback from uma(9), called on alloc. */ 119 static int 120 uma_ctor_flow(void *mem, int size, void *arg, int how) 121 { 122 priv_p priv = (priv_p )arg; 123 124 if (atomic_load_acq_32(&priv->info.nfinfo_used) >= CACHESIZE) 125 return (ENOMEM); 126 127 atomic_add_32(&priv->info.nfinfo_used, 1); 128 129 return (0); 130 } 131 132 /* This is callback from uma(9), called on free. */ 133 static void 134 uma_dtor_flow(void *mem, int size, void *arg) 135 { 136 priv_p priv = (priv_p )arg; 137 138 atomic_subtract_32(&priv->info.nfinfo_used, 1); 139 } 140 141 /* 142 * Detach export datagram from priv, if there is any. 143 * If there is no, allocate a new one. 144 */ 145 static item_p 146 get_export_dgram(priv_p priv) 147 { 148 item_p item = NULL; 149 150 mtx_lock(&priv->export_mtx); 151 if (priv->export_item != NULL) { 152 item = priv->export_item; 153 priv->export_item = NULL; 154 } 155 mtx_unlock(&priv->export_mtx); 156 157 if (item == NULL) { 158 struct netflow_v5_export_dgram *dgram; 159 struct mbuf *m; 160 161 m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR); 162 if (m == NULL) 163 return (NULL); 164 item = ng_package_data(m, NG_NOFLAGS); 165 if (item == NULL) 166 return (NULL); 167 dgram = mtod(m, struct netflow_v5_export_dgram *); 168 dgram->header.count = 0; 169 dgram->header.version = htons(NETFLOW_V5); 170 171 } 172 173 return (item); 174 } 175 176 /* 177 * Re-attach incomplete datagram back to priv. 178 * If there is already another one, then send incomplete. */ 179 static void 180 return_export_dgram(priv_p priv, item_p item) 181 { 182 /* 183 * It may happen on SMP, that some thread has already 184 * put its item there, in this case we bail out and 185 * send what we have to collector. 186 */ 187 mtx_lock(&priv->export_mtx); 188 if (priv->export_item == NULL) { 189 priv->export_item = item; 190 mtx_unlock(&priv->export_mtx); 191 } else { 192 mtx_unlock(&priv->export_mtx); 193 export_send(priv, item); 194 } 195 } 196 197 /* 198 * The flow is over. Call export_add() and free it. If datagram is 199 * full, then call export_send(). 200 */ 201 static __inline void 202 expire_flow(priv_p priv, item_p *item, struct flow_entry *fle) 203 { 204 if (*item == NULL) 205 *item = get_export_dgram(priv); 206 if (*item == NULL) { 207 atomic_add_32(&priv->info.nfinfo_export_failed, 1); 208 uma_zfree_arg(priv->zone, fle, priv); 209 return; 210 } 211 if (export_add(*item, fle) > 0) { 212 export_send(priv, *item); 213 *item = NULL; 214 } 215 uma_zfree_arg(priv->zone, fle, priv); 216 } 217 218 /* Get a snapshot of node statistics */ 219 void 220 ng_netflow_copyinfo(priv_p priv, struct ng_netflow_info *i) 221 { 222 /* XXX: atomic */ 223 memcpy((void *)i, (void *)&priv->info, sizeof(priv->info)); 224 } 225 226 /* Calculate number of bits in netmask */ 227 #define g21 0x55555555ul /* = 0101_0101_0101_0101_0101_0101_0101_0101 */ 228 #define g22 0x33333333ul /* = 0011_0011_0011_0011_0011_0011_0011_0011 */ 229 #define g23 0x0f0f0f0ful /* = 0000_1111_0000_1111_0000_1111_0000_1111 */ 230 static __inline u_char 231 bit_count(uint32_t v) 232 { 233 v = (v & g21) + ((v >> 1) & g21); 234 v = (v & g22) + ((v >> 2) & g22); 235 v = (v + (v >> 4)) & g23; 236 return (v + (v >> 8) + (v >> 16) + (v >> 24)) & 0x3f; 237 } 238 239 /* 240 * Insert a record into defined slot. 241 * 242 * First we get for us a free flow entry, then fill in all 243 * possible fields in it. 244 * 245 * TODO: consider dropping hash mutex while filling in datagram, 246 * as this was done in previous version. Need to test & profile 247 * to be sure. 248 */ 249 static __inline int 250 hash_insert(priv_p priv, struct flow_hash_entry *hsh, struct flow_rec *r, 251 int plen, uint8_t tcp_flags) 252 { 253 struct flow_entry *fle; 254 struct route ro; 255 struct sockaddr_in *sin; 256 257 mtx_assert(&hsh->mtx, MA_OWNED); 258 259 fle = uma_zalloc_arg(priv->zone, priv, M_NOWAIT); 260 if (fle == NULL) { 261 atomic_add_32(&priv->info.nfinfo_alloc_failed, 1); 262 return (ENOMEM); 263 } 264 265 /* 266 * Now fle is totally ours. It is detached from all lists, 267 * we can safely edit it. 268 */ 269 270 bcopy(r, &fle->f.r, sizeof(struct flow_rec)); 271 fle->f.bytes = plen; 272 fle->f.packets = 1; 273 fle->f.tcp_flags = tcp_flags; 274 275 fle->f.first = fle->f.last = time_uptime; 276 277 /* 278 * First we do route table lookup on destination address. So we can 279 * fill in out_ifx, dst_mask, nexthop, and dst_as in future releases. 280 */ 281 bzero((caddr_t)&ro, sizeof(ro)); 282 sin = (struct sockaddr_in *)&ro.ro_dst; 283 sin->sin_len = sizeof(*sin); 284 sin->sin_family = AF_INET; 285 sin->sin_addr = fle->f.r.r_dst; 286 rtalloc_ign(&ro, RTF_CLONING); 287 if (ro.ro_rt != NULL) { 288 struct rtentry *rt = ro.ro_rt; 289 290 fle->f.fle_o_ifx = rt->rt_ifp->if_index; 291 292 if (rt->rt_flags & RTF_GATEWAY && 293 rt->rt_gateway->sa_family == AF_INET) 294 fle->f.next_hop = 295 ((struct sockaddr_in *)(rt->rt_gateway))->sin_addr; 296 297 if (rt_mask(rt)) 298 fle->f.dst_mask = 299 bit_count(((struct sockaddr_in *)rt_mask(rt))->sin_addr.s_addr); 300 else if (rt->rt_flags & RTF_HOST) 301 /* Give up. We can't determine mask :( */ 302 fle->f.dst_mask = 32; 303 304 RTFREE(ro.ro_rt); 305 } 306 307 /* Do route lookup on source address, to fill in src_mask. */ 308 309 bzero((caddr_t)&ro, sizeof(ro)); 310 sin = (struct sockaddr_in *)&ro.ro_dst; 311 sin->sin_len = sizeof(*sin); 312 sin->sin_family = AF_INET; 313 sin->sin_addr = fle->f.r.r_src; 314 rtalloc_ign(&ro, RTF_CLONING); 315 if (ro.ro_rt != NULL) { 316 struct rtentry *rt = ro.ro_rt; 317 318 if (rt_mask(rt)) 319 fle->f.src_mask = 320 bit_count(((struct sockaddr_in *)rt_mask(rt))->sin_addr.s_addr); 321 else if (rt->rt_flags & RTF_HOST) 322 /* Give up. We can't determine mask :( */ 323 fle->f.src_mask = 32; 324 325 RTFREE(ro.ro_rt); 326 } 327 328 /* Push new flow at the and of hash. */ 329 TAILQ_INSERT_TAIL(&hsh->head, fle, fle_hash); 330 331 return (0); 332 } 333 334 335 /* 336 * Non-static functions called from ng_netflow.c 337 */ 338 339 /* Allocate memory and set up flow cache */ 340 int 341 ng_netflow_cache_init(priv_p priv) 342 { 343 struct flow_hash_entry *hsh; 344 int i; 345 346 /* Initialize cache UMA zone. */ 347 priv->zone = uma_zcreate("NetFlow cache", sizeof(struct flow_entry), 348 uma_ctor_flow, uma_dtor_flow, NULL, NULL, UMA_ALIGN_CACHE, 0); 349 uma_zone_set_max(priv->zone, CACHESIZE); 350 351 /* Allocate hash. */ 352 MALLOC(priv->hash, struct flow_hash_entry *, 353 NBUCKETS * sizeof(struct flow_hash_entry), 354 M_NETFLOW_HASH, M_WAITOK | M_ZERO); 355 356 if (priv->hash == NULL) { 357 uma_zdestroy(priv->zone); 358 return (ENOMEM); 359 } 360 361 /* Initialize hash. */ 362 for (i = 0, hsh = priv->hash; i < NBUCKETS; i++, hsh++) { 363 mtx_init(&hsh->mtx, "hash mutex", NULL, MTX_DEF); 364 TAILQ_INIT(&hsh->head); 365 } 366 367 mtx_init(&priv->export_mtx, "export dgram lock", NULL, MTX_DEF); 368 369 return (0); 370 } 371 372 /* Free all flow cache memory. Called from node close method. */ 373 void 374 ng_netflow_cache_flush(priv_p priv) 375 { 376 struct flow_entry *fle, *fle1; 377 struct flow_hash_entry *hsh; 378 item_p item = NULL; 379 int i; 380 381 /* 382 * We are going to free probably billable data. 383 * Expire everything before freeing it. 384 * No locking is required since callout is already drained. 385 */ 386 for (hsh = priv->hash, i = 0; i < NBUCKETS; hsh++, i++) 387 TAILQ_FOREACH_SAFE(fle, &hsh->head, fle_hash, fle1) { 388 TAILQ_REMOVE(&hsh->head, fle, fle_hash); 389 expire_flow(priv, &item, fle); 390 } 391 392 if (item != NULL) 393 export_send(priv, item); 394 395 uma_zdestroy(priv->zone); 396 397 /* Destroy hash mutexes. */ 398 for (i = 0, hsh = priv->hash; i < NBUCKETS; i++, hsh++) 399 mtx_destroy(&hsh->mtx); 400 401 /* Free hash memory. */ 402 if (priv->hash) 403 FREE(priv->hash, M_NETFLOW_HASH); 404 405 mtx_destroy(&priv->export_mtx); 406 } 407 408 /* Insert packet from into flow cache. */ 409 int 410 ng_netflow_flow_add(priv_p priv, struct ip *ip, iface_p iface, 411 struct ifnet *ifp) 412 { 413 register struct flow_entry *fle, *fle1; 414 struct flow_hash_entry *hsh; 415 struct flow_rec r; 416 item_p item = NULL; 417 int hlen, plen; 418 int error = 0; 419 uint8_t tcp_flags = 0; 420 421 /* Try to fill flow_rec r */ 422 bzero(&r, sizeof(r)); 423 /* check version */ 424 if (ip->ip_v != IPVERSION) 425 return (EINVAL); 426 427 /* verify min header length */ 428 hlen = ip->ip_hl << 2; 429 430 if (hlen < sizeof(struct ip)) 431 return (EINVAL); 432 433 r.r_src = ip->ip_src; 434 r.r_dst = ip->ip_dst; 435 436 /* save packet length */ 437 plen = ntohs(ip->ip_len); 438 439 r.r_ip_p = ip->ip_p; 440 r.r_tos = ip->ip_tos; 441 442 /* Configured in_ifx overrides mbuf's */ 443 if (iface->info.ifinfo_index == 0) { 444 if (ifp != NULL) 445 r.r_i_ifx = ifp->if_index; 446 } else 447 r.r_i_ifx = iface->info.ifinfo_index; 448 449 /* 450 * XXX NOTE: only first fragment of fragmented TCP, UDP and 451 * ICMP packet will be recorded with proper s_port and d_port. 452 * Following fragments will be recorded simply as IP packet with 453 * ip_proto = ip->ip_p and s_port, d_port set to zero. 454 * I know, it looks like bug. But I don't want to re-implement 455 * ip packet assebmling here. Anyway, (in)famous trafd works this way - 456 * and nobody complains yet :) 457 */ 458 if ((ip->ip_off & htons(IP_OFFMASK)) == 0) 459 switch(r.r_ip_p) { 460 case IPPROTO_TCP: 461 { 462 register struct tcphdr *tcp; 463 464 tcp = (struct tcphdr *)((caddr_t )ip + hlen); 465 r.r_sport = tcp->th_sport; 466 r.r_dport = tcp->th_dport; 467 tcp_flags = tcp->th_flags; 468 break; 469 } 470 case IPPROTO_UDP: 471 r.r_ports = *(uint32_t *)((caddr_t )ip + hlen); 472 break; 473 } 474 475 /* Update node statistics. XXX: race... */ 476 priv->info.nfinfo_packets ++; 477 priv->info.nfinfo_bytes += plen; 478 479 /* Find hash slot. */ 480 hsh = &priv->hash[ip_hash(&r)]; 481 482 mtx_lock(&hsh->mtx); 483 484 /* 485 * Go through hash and find our entry. If we encounter an 486 * entry, that should be expired, purge it. We do a reverse 487 * search since most active entries are first, and most 488 * searches are done on most active entries. 489 */ 490 TAILQ_FOREACH_REVERSE_SAFE(fle, &hsh->head, fhead, fle_hash, fle1) { 491 if (bcmp(&r, &fle->f.r, sizeof(struct flow_rec)) == 0) 492 break; 493 if ((INACTIVE(fle) && SMALL(fle)) || AGED(fle)) { 494 TAILQ_REMOVE(&hsh->head, fle, fle_hash); 495 expire_flow(priv, &item, fle); 496 atomic_add_32(&priv->info.nfinfo_act_exp, 1); 497 } 498 } 499 500 if (fle) { /* An existent entry. */ 501 502 fle->f.bytes += plen; 503 fle->f.packets ++; 504 fle->f.tcp_flags |= tcp_flags; 505 fle->f.last = time_uptime; 506 507 /* 508 * We have the following reasons to expire flow in active way: 509 * - it hit active timeout 510 * - a TCP connection closed 511 * - it is going to overflow counter 512 */ 513 if (tcp_flags & TH_FIN || tcp_flags & TH_RST || AGED(fle) || 514 (fle->f.bytes >= (UINT_MAX - IF_MAXMTU)) ) { 515 TAILQ_REMOVE(&hsh->head, fle, fle_hash); 516 expire_flow(priv, &item, fle); 517 } else { 518 /* 519 * It is the newest, move it to the tail, 520 * if it isn't there already. Next search will 521 * locate it quicker. 522 */ 523 if (fle != TAILQ_LAST(&hsh->head, fhead)) { 524 TAILQ_REMOVE(&hsh->head, fle, fle_hash); 525 TAILQ_INSERT_TAIL(&hsh->head, fle, fle_hash); 526 } 527 } 528 } else /* A new flow entry. */ 529 error = hash_insert(priv, hsh, &r, plen, tcp_flags); 530 531 mtx_unlock(&hsh->mtx); 532 533 if (item != NULL) 534 return_export_dgram(priv, item); 535 536 return (error); 537 } 538 539 /* 540 * Return records from cache to userland. 541 * 542 * TODO: consider NGM_READONLY 543 * TODO: matching particular IP should be done in kernel, here. 544 */ 545 int 546 ng_netflow_flow_show(priv_p priv, uint32_t last, struct ng_mesg *resp) 547 { 548 struct flow_hash_entry *hsh; 549 struct flow_entry *fle; 550 struct ngnf_flows *data; 551 int i; 552 553 data = (struct ngnf_flows *)resp->data; 554 data->last = 0; 555 data->nentries = 0; 556 557 /* Check if this is a first run */ 558 if (last == 0) { 559 hsh = priv->hash; 560 i = 0; 561 } else { 562 if (last > NBUCKETS-1) 563 return (EINVAL); 564 hsh = priv->hash + last; 565 i = last; 566 } 567 568 /* 569 * We will transfer not more than NREC_AT_ONCE. More data 570 * will come in next message. 571 * We send current hash index to userland, and userland should 572 * return it back to us. Then, we will restart with new entry. 573 * 574 * The resulting cache snapshot is inaccurate for the 575 * following reasons: 576 * - we skip locked hash entries 577 * - we bail out, if someone wants our entry 578 * - we skip rest of entry, when hit NREC_AT_ONCE 579 */ 580 for (; i < NBUCKETS; hsh++, i++) { 581 if (mtx_trylock(&hsh->mtx) == 0) 582 continue; 583 584 TAILQ_FOREACH(fle, &hsh->head, fle_hash) { 585 if (hsh->mtx.mtx_lock & MTX_CONTESTED) 586 break; 587 588 bcopy(&fle->f, &(data->entries[data->nentries]), 589 sizeof(fle->f)); 590 data->nentries++; 591 if (data->nentries == NREC_AT_ONCE) { 592 mtx_unlock(&hsh->mtx); 593 if (++i < NBUCKETS) 594 data->last = i; 595 return (0); 596 } 597 } 598 mtx_unlock(&hsh->mtx); 599 } 600 601 return (0); 602 } 603 604 /* We have full datagram in privdata. Send it to export hook. */ 605 static int 606 export_send(priv_p priv, item_p item) 607 { 608 struct mbuf *m = NGI_M(item); 609 struct netflow_v5_export_dgram *dgram = mtod(m, 610 struct netflow_v5_export_dgram *); 611 struct netflow_v5_header *header = &dgram->header; 612 struct timespec ts; 613 int error = 0; 614 615 /* Fill mbuf header. */ 616 m->m_len = m->m_pkthdr.len = sizeof(struct netflow_v5_record) * 617 header->count + sizeof(struct netflow_v5_header); 618 619 /* Fill export header. */ 620 header->sys_uptime = htonl(MILLIUPTIME(time_uptime)); 621 getnanotime(&ts); 622 header->unix_secs = htonl(ts.tv_sec); 623 header->unix_nsecs = htonl(ts.tv_nsec); 624 header->count = htons(header->count); 625 header->flow_seq = htonl(atomic_load_acq_32(&priv->flow_seq)); 626 627 /* Flow sequence contains number of first record, so it 628 is updated after being put in header. */ 629 atomic_add_32(&priv->flow_seq, header->count); 630 631 if (priv->export != NULL) 632 /* Should also NET_LOCK_GIANT(). */ 633 NG_FWD_ITEM_HOOK(error, item, priv->export); 634 635 return (error); 636 } 637 638 639 /* Add export record to dgram. */ 640 static int 641 export_add(item_p item, struct flow_entry *fle) 642 { 643 struct netflow_v5_export_dgram *dgram = mtod(NGI_M(item), 644 struct netflow_v5_export_dgram *); 645 struct netflow_v5_header *header = &dgram->header; 646 struct netflow_v5_record *rec; 647 648 if (header->count == 0 ) { /* first record */ 649 rec = &dgram->r[0]; 650 header->count = 1; 651 } else { /* continue filling datagram */ 652 rec = &dgram->r[header->count]; 653 header->count ++; 654 } 655 656 KASSERT(header->count <= NETFLOW_V5_MAX_RECORDS, 657 ("ng_netflow: export too big")); 658 659 /* Fill in export record. */ 660 rec->src_addr = fle->f.r.r_src.s_addr; 661 rec->dst_addr = fle->f.r.r_dst.s_addr; 662 rec->next_hop = fle->f.next_hop.s_addr; 663 rec->i_ifx = htons(fle->f.fle_i_ifx); 664 rec->o_ifx = htons(fle->f.fle_o_ifx); 665 rec->packets = htonl(fle->f.packets); 666 rec->octets = htonl(fle->f.bytes); 667 rec->first = htonl(MILLIUPTIME(fle->f.first)); 668 rec->last = htonl(MILLIUPTIME(fle->f.last)); 669 rec->s_port = fle->f.r.r_sport; 670 rec->d_port = fle->f.r.r_dport; 671 rec->flags = fle->f.tcp_flags; 672 rec->prot = fle->f.r.r_ip_p; 673 rec->tos = fle->f.r.r_tos; 674 rec->dst_mask = fle->f.dst_mask; 675 rec->src_mask = fle->f.src_mask; 676 677 /* Not supported fields. */ 678 rec->src_as = rec->dst_as = 0; 679 680 if (header->count == NETFLOW_V5_MAX_RECORDS) 681 return (1); /* end of datagram */ 682 else 683 return (0); 684 } 685 686 /* Periodic flow expiry run. */ 687 void 688 ng_netflow_expire(void *arg) 689 { 690 struct flow_entry *fle, *fle1; 691 struct flow_hash_entry *hsh; 692 priv_p priv = (priv_p )arg; 693 item_p item = NULL; 694 uint32_t used; 695 int i; 696 697 /* 698 * Going through all the cache. 699 */ 700 for (hsh = priv->hash, i = 0; i < NBUCKETS; hsh++, i++) { 701 /* 702 * Skip entries, that are already being worked on. 703 */ 704 if (mtx_trylock(&hsh->mtx) == 0) 705 continue; 706 707 used = atomic_load_acq_32(&priv->info.nfinfo_used); 708 TAILQ_FOREACH_SAFE(fle, &hsh->head, fle_hash, fle1) { 709 /* 710 * Interrupt thread wants this entry! 711 * Quick! Quick! Bail out! 712 */ 713 if (hsh->mtx.mtx_lock & MTX_CONTESTED) 714 break; 715 716 /* 717 * Don't expire aggressively while hash collision 718 * ratio is predicted small. 719 */ 720 if (used <= (NBUCKETS*2) && !INACTIVE(fle)) 721 break; 722 723 if ((INACTIVE(fle) && (SMALL(fle) || (used > (NBUCKETS*2)))) || 724 AGED(fle)) { 725 TAILQ_REMOVE(&hsh->head, fle, fle_hash); 726 expire_flow(priv, &item, fle); 727 used--; 728 atomic_add_32(&priv->info.nfinfo_inact_exp, 1); 729 } 730 } 731 mtx_unlock(&hsh->mtx); 732 } 733 734 if (item != NULL) 735 return_export_dgram(priv, item); 736 737 /* Schedule next expire. */ 738 callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire, 739 (void *)priv); 740 }
Cache object: 8dfaebe9fa3f7f9a49b58d27aefbc2df
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